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"entral Library System
Jniversity of Wisconsin-Madisoi
/28 State Street
Madison, Wi 53706-1494
U.S.A.
iT*. J. „
THE
COLUMBIA RIVER
INTERSTATE BRIDGE
FINAL REPORT
in
it
11
SI
Si
FINAL REPORT
The Columbia River Interstate Bridge
Vancouver, Washington to Portland, Oregon
FOR
Multnomah County, Oregon
Clarke County, Washington
BY
JOHN LYLEiHARRINGTON AND ERNEST E. HOWARD
CONSULTING ENGINEERS. KANSAS CITY. MO.
Copyright, 1918
by
JOHN LYLE HARRINGTON
AND ERNEST E. HOWARD
THE COLUMBIA RIVER
INTERSTATE BRIDGE COMMISSION
PERSONNEL
From Nomember, 1913, to January, 1915.
Rufus C. Holman, Chairman;
W. L. Lightner,
D. V. Hart,
Governor Oswald West,
A. Rawson,
W. S. Lindsay,
S. N. Secrist,
Commissioners for Multnomah
County.
Commissioners for Clarke
County.
W. N. Marshall, Secretary.
From January, 1915, to January, 1917.
Rufus C. Holman, Chairman;
W. L. Lightner,
Philo M. Holbrook,
Governor Jas. B. Withycombe,
A. Rawson,
W. S. Lindsay,
John P. Kiggins,
Commissioners for Multnomah
County.
Conunissioners for Clarke
County.
After January, 1917.
Rufus C. Holman, Chairman;
Philo M. Holbrook,
A. A. Muck,
Governor Jas. B. Withycombe,
M. E. Carson,
Abe Miller,
John P. Kiggins,
Commissioners for Multnomah
County.
Commissioners for Clarke
County.
Legal Advisers : Walter H. Evans, Arthur A. Murphy, James
O. Blair, L. M. Burnett.
GENERAL CALENDAR OF EVENTS
Auguii^t
12« 1913« Clarke County, Washington voted bonds
for construction.
Sove.mhev 4« 1913, Multnomah County, Oregon, voted bonds
for construction.
Nov<*mber 29, 1913, The Columbia River Interstate Bridge
Commission organized.
Deci'inber 29, 1913, Commission selected Engineers.
I)c*c(»mbcr 29, 1913, Commission directed Engineers to prepare
preliminary plans and to make a report
recommending a location for bridge and
approaches.
Jiinuiiry 31, 1914, Hill authorizing construction passed Con-
gress.
March
26, 1914, Engineers completed preliminary studies,
and recommended location of structure.
Mnrcli 30, 1914, Commission adopted report and located
structure.
April 13, 1914, Engineers made application to Secretary
of War for permit for construction.
20, 1914, Public hearing of War Department to con-
sider proposed plans.
12, 1914, Tentative approval of plans given by Sec-
retary of War.
Progress delayed by financial disturbance
due to commencement of war in Europe.
Nc)vt nibor. 1914, Chirke County sold $250,000 bridge bonds.
April
,Iuue
November
9, 1914, Multnomah County sold $250,000 bridge
bonds.
December, 1914, Clarke County sold $250,000 bridge bonds.
December 14, 1914, Multnomah County sold $1,000,000 bridge
bonds.
8
January-
January
11, 1915, Engineers presented final detailed plans
and specifications.
11, 1915, Commission adopted plans and specifica-
tions and ordered work advertised.
February 23, 1915, Commission received bids for all principal
construction work.
February 27, 1915, ConMnission awarded contracts for princi-
pal construction work.
March
April
April
April
June
6, 1915, Actual construction formally started.
2, 1915, Engineers presented and Commission
adopted plans and specifications for Derby
Street approach embankment.
26, 1915, Commission received bids for Derby Street
approach embankment.
30, 1915, Commission awarded contract Derby Street
approach embankment.
16, 1915, Final approval of plans given by Secretary
of War.
August
18, 1916, Engineers presented and Commission
adopted plans and specifications for pave-
ment of approach embankments.
September 19, 1916, Commission received bids for pavement of
approach embankments.
September 20, 1916, Commission awarded contract for pave-
ment of approach embankments.
October 27, 1916, ConMnission awarded contract making pur-
chase of materials for lighting system.
March
6, 1917, ConMnission awarded contract for con
structing lighting system.
February 14, 1917, Bridge formally opened to traftic.
August
2, 1917, Engineers rendered final estimate for last
contract.
9
CONTENTS
PAGE
Personnel of Columbia River Interstate Bridge Commission 7
General Calendar of Events 8
Inscriptions 11
Introduction 13
General Statement 15
Description of Bridge 21
Loads for Which the Bridge is Designed 32
Special Features of Design _• 34
Construction Methods and Experiences 37
Franchise to Street Car Company _ 45
Right-of-Way 47
Quantities 48
Cost of Construction 51
Maintenance 55
Tolls 59
Income and Traffic 60
Lift Span Movements 61
ILLUSTRATIONS
PAGE
Columbia River Interstate Bridge Frontispiece
Vancouver End of Columbia River Bridge 12
Oregon Slough Bridge as seen from Hayden Island _12
Columbia River Bridge as seen from Vancouver 19
Drawing, Floor Construction of Truss Spans 23
Lift Span Operating Machinery Assembled in. Shop 24
Columbia River Bridge as seen from Vancouver 26
Drawing, Details of Typical Pier 28
Construction of Union Avenue Approach Embankment 30
Pile Driver Equipment used in Building Piers 34
Manufacturing the Steel, Trusses Assembled at Bridge Shop 36
Building the Piers, Removing Cofferdam 37
Erecting Through Truss Spans on Shore 39
Truss Spans on Launching Ways Ready for Moving 40
Moving Completed Span Across River on Barges 41
Embankment Construction, Bulkheads and Methods of Deposit 43
Completed Embankment along Union Avenue Approach 44
Opening Day Columbia River Interstate Bridge 01
10
1915
THIS BRIDGE IS DEDICATED TO THE
CITIZENS OF OREGON AND WASHINGTON BY
WHOM ITS ERECTION WAS ORDAINED. IT WAS
CONCEIVED OF THEIR VISION, ITS FOUNDA-
TIONS ARE LAID UPON THEIR SACRIFICES.
THE SPIRITUAL HERITAGE OF COURAGE, FAITH
AND HIGH ENDEAVOR BEQUEATHED TO THIS
GENERATION BY THE PIONEERS WHO WRESTED
FROM THE WILDERNESS THESE WIDE AND FRUIT-
FUL LANDS, IS BUILDED INTO ITS MEMBERS
OF STONE AND STEEL AND HERE HANDED DOWN
TO THE GENERATIONS THAT COME AFTER.
1917
THE COLUMBIA RIVER INTERSTATE BRIDGE
BUILT BY THE PEOPLE OF CLARKE COUNTY
WASHINGTON.ANDMULTNOMAHCOUNTYOREGON,
UNDER DIRECTION OF THE COLUMBIA RIVER
INTERSTATE BRIDGE COMMISSION, RUFUS C
HOLMAN, CHAIRMAN, COMMISSIONERS FOR
CLARKE COUNTY, A. RAWSON, CHAIRMAN. W S.
LINDSAY, JOHN P. KIGGINS. COMMISSIONERS
FOR MULTNOMAH COUNTY, W. L. LIGHTNER.
CHAIRMAN, PHILO HOLBROOK, RUFUS C. HOLMAN.
THE GOVERNOR OF OREGON. LEGAL ADVISERS.
WALTER H. EVANS, JAMES O. BLAIR. ARTHUR
MURPHY. CONSTRUCTION BEGAN MARCH. 191S.
COMPLETED JANUARY, 1917.
THE COLUMBIA RIVER INTERSTATE BRIDGE
DESIGNED AND BUILT UNDER DIRECTION OF
JOHN LYLE HARRINGTON. KANSAS CITY, MO.,
WADDELL & HARRINGTON (NOW DISSOLVED ) ,L0 UIS
R. ASH & ERNEST E. HOWARD, CONSULTING
ENGINEERS. F. M. CORTELYOU. RESDT. ENGR.
CONTRACTORS: MANUFACTURE OF STEEL.
AMERICAN BRIDGE COMPANY. NORTHWEST STEEL
COMPANY. ERECTION, PORTER BROTHERS.
FOUNDATIONS. THE PACIFIC BRIDGE COMPANY.
EMBANKMENTS. TACOMA DREDGING COMPANY,
STANDARD AMERICAN DREDGING COMPANY.
PAVEMENTS, WARREN CONSTRUCTION COMPANY.
"OF ALL INVENTIONS, THE ALPHABET
AND THE PRINTING PRESS ALONE EXCEPTED,
THOSE INVENTIONS WHICH ABRIDGE DISTANCE
HAVE DONE MOST FOR THE CIVILISATION OF
OUR SPECIES. EVERY IMPROVEMENT OF THE
MEANS OF LOCOMOTION BENEFITS MANKIND
MORALLY AND INTELLECTUALLY AS WELL AS
MATERIALLY, AND NOT ONLY FACILITATES
THE INTERCHANGE OF THE VARIOUS PRODUC-
TIONS OF NATURE AND ART, BUT TENDS TO
REMOVE NATIONAL AND PROVINCIAL ANTIPA-
THIES, AND TO BIND TOGETHER ALL THE
BRANCHES OF THE GREAT HUMAN FAMILY."
— MACAULAY.
THE COLUMBIA RIVER INTERSTATE BRIDGE.
TOTAL LENGTH OF BRIDGE AND APPROACHES
4^ MILES. COMPLETED JANUARY, 1917. TOTAL
COST $1,760,000. THE BRIDGE OVER THE COLUM-
BIA RIVER 3,531 FT. LONG. CONSISTS OF ONE 50
FT. SPAN, THREE 275 FT. SPANS AND TEN 265 FT.
SPANS; AND CONTAINS 7350 TONS OF STEEL,
17.650 SQ. YDS. OF REINFORCED CONCRETE
DECK, 15.000 SQ. YDS. OF PAVEMENT. 21.600 CU.
YDS. OF PIERS SUPPORTED ON PILES EXTEND-
ING TO 160 FT. BELOW ROADWAY. THE TOWERS
EXTEND TO 190 FT. ABOVE ROADWAY.
"YOU MAY TELL ME THAT MY VIEWS ARE
VISIONARY. THAT THE DESTINY OF THIS COUN-
TRY IS LESS EXALTED. THAT THE AMERICAN
PEOPLE ARE LESS GREAT THAN I THINK THEY
ARE OR OUGHT TO BE. I ANSWER. IDEALS ARE
LIKE STARS. YOU WILL NOT SUCCEED IN TOUCH-
ING THEM WITH YOUR HANDS. BUT LIKE THE
SEA-FARING MAN ON THE DESERT OF WATERS.
YOU CHOOSE THEM AS YOUR GUIDES AND
FOLLOWING THEM, YOU REACH YOUR DESTINY."
-CARL SCHURZ.
THE COLUMBIA RIVEt) INTERSTATE BRIDGE
APPROACHES
THE BRIDGE OVER OREGON SLOUGH. 1.137 FT.
LONG. CONSISTS OF ONE 115 FT. SPAN AND TEN
100 FT. SPANS. THE BRIDGE OVER COLUMBIA
SLOUGH IS 307 FT. LONG AND CONSISTS OF FOUR
75 FT. SPANS. THESE BRIDGES CONTAIN 1,725
TONS OF STEEL. 7.150 SQ. YDS. OF REINFORCED
CONCRETE DECK. 6,100 SQ. YDS. OF PAVEMENT,
5,700 CU. YDS. OF PIERS. THE EMBANKMENTS
HAVE A COMBINED LENGTH OF 18.000 FT. AND
CONTAIN 1,500,000 CU. YDS. PAVEMENT ON EM-
BANKMENTS 56.000 SQ. YDS.
"THEREFORE WHEN WE BUILD. LET
US THINK THAT WE BUILD FOREVER. LET
IT NOT BE FOR PRESENT DELIGHT, NOR
FOR PRESENT USE ALONE. LET IT BE SUCH
WORK AS OUR DESCENDANTS WILL THANK US
FOR, AND LET US THINK, AS WE LAY STONE
ON STONE, THAT A TIME IS TO COME WHEN
THOSE STONES WILL BE HELD SACRED BE-
CAUSE OUR HANDS HAVE TOUCHED THEM, AND
THAT MEN WILL SAY AS THEY LOOK UPON
THE LABOR. AND WROUGHT SUBSTANCE OF
THEM. 'SEE THIS OUR FATHERS DID FOR
US.'"
— RUSKIN.
These inscripbons on bronze tablets are on the entrance columns of the bridge.
11
VANCOUVER END OP I
I fniiti Hayden
The Columbia River Interstate Bridge Commission,
The Commissioners of Multnomah County, Oregon,
The Commissioners of Clarke County, Washington,
Gentlemen :
The Columbia River Interstate Bridge between Vancouver,
Washington, and Portland, Oregon, is completed and in service.
We now respectfully submit our final report upon all the prin-
cipal matters pertaining to its construction. Beginning with our
report of March 26, 1914, recommending the adopted loca-
tion of the bridge and its approaches, we have made many
reports to you, including regular weekly reports showing the
progress of the work included under each contract, monthly
reports and estimates showing the amounts earned by each con-
tractor, reports relating to tests and inspection of materials and
workmanship, and various special reports on rights of way, fran-
chises, operation, and similar matters. These are all in your
files and available for reference; hence their details will not be
repeated; but this report will be confined to the more important
engineering and business features of the whole project, includ-
ing your own actions.
The efficient and harmonious working of the Columbia
River Interstate Bridge Commission has been largely responsi-
ble for the success and celerity with which the work has been
carried out. Although composed of the Commissions of two
counties situated in different states, having different laws and
different interests, differing greatly in wealth and jiopulation,
and contributing different sums of money, we have found the
Commissioners, while jealous of the rights and tenacious of the
prerogatives of the community each represented, always fair
and reasonable and ready to find some common equable ground
for adjusting differences so as to permit the work to go forward.
The eminently satisfactory progress and conclusion of the work
could not have been attained except for the promptness of the
Conmniission in deciding the many questions presented, and for
the unwavering firmness with which the Commission adhered
to a position adopted or a policy determined. We have been
highly gratified to have the Commission adopt, we believe with-
out exception, our every recommendation.
The care and attention to detail which marked the execu-
tion of the design and other technical features are evident in the
13
completed structure, and are also indicated in the financial state-
ment. Beginning with an amount of money insufficient, accord-
ing to early reports, even for a bridge with a 24-ft. roadway
and one approach on the Oregon side (main bridge, $1,660,700;
Oregon approach, $420,000), the design both of substructure and
superstructure proved to be so fitting and economical and con-
ditions for construction according to these designs so favorable,
that the bridge was completed with a 38-f t. roadway, with con-
crete floor, wholly fire-proof, and with two approaches on the
Oregon side, within the funds ($1,790,000) and with a balance
of the original fund left with each county (totaling $56,000).
But we have attempted to serve you broadly; not alone along
technical lines, but in the administration and in the general busi-
ness of buying a bridge and getting full value for the money
spent; in the study of the broad and general needs of the public
for transportation facilities, which was a large factor in deter-
mining the recommendation for the location of the bridge and
approaches, in assisting with negotiations for the acquirement
of the rights-of-way and other properties; in drafting tentative
franchises for street railway operation; in the determination of
tolls to be charged; in arranging a scheme of organization for
the operating department, and in the general problems of admin-
istration. We have tried always to give the same careful and
detailed attention to every question submitted to us as we have
to essentially engineering problems. In this connection, we
would like to add, that never in a long experience of similar
undertakings have we known more sympathetic, broad-minded
and intelligent co-operation from a legal department than you
have received and we have enjoyed at the hands of Mr. Walter
H. Evans, District Attorney, and his associates.
The Columbia River Interstate Bridge is a great public work
carried through with intelligence, economy and efficiency. It
should always be a source of gratification and pride to the mem-
bers of the Columbia River Interstate Bridge Commission, for it
cannot but long be known as a monument to their public service.
Respectfully submitted,
John Lyle Harrington,
Ernest E. Howard,
Consulting Engineers.
14
GENERAL STATEMENT
The Columbia River Interstate Bridge is in some respects
unique as a public work; unique in the persistence and unanim-
ity of the people of Clarke County and Multnomah County in
providing for its construction; unique in the celerity of the pub-
lic officers in organizing and pushing forward with the work;
unique in the rapidity of construction; unique in the fact that
the entire work originally contemplated and a complete addi-
tional approach were constructed within the money provided;
and unique in proving to be a paying investment, with a con-
stantly increasing income. It is also the first and the only high-
way bridge over the Columbia River from far above the mouth
of the Snake River to the Pacific Ocean.
For many years the Columbia River was crossed only by fer-
ries. At length a railroad bridge was built at Vancouver, and
one or two up the river, but the highway traffic was still confined
to the ferries. With increase of population and of travel, and
the widespread and growing realization of the need for im-
proved highways, there came to be a general recognition of the
necessities for and of the advantages certain to follow the con-
struction of a highway bridge over the Columbia River at Van-
couver. Actively advocated by an increasing number of men
well known in Oregon and Washington, the demand for a bridge
became crystallized, during the early months of 1912, in a move-
ment by the Commercial Club of Vancouver, Washington, and
the then Conmiercial Club of Portland, Oregon, which finally
resulted in the enactment of laws by the States of Washington
and Oregon permitting Clarke County, Washington, and Mult-
nomah County, Oregon, to provide funds by voting bonds and to
join in the construction of a bridge. (Laws of Washington 1913,
Chapter 56, page 168; Laws of Oregon 1913, Chapter 349, page
701.) Active campaigns for immediate action under these stat-
utes were conducted by the two organizations and received
hearty endorsement from the citizenship, for on August 12, 1913,
Clarke County voted overwhelmingly for the issuance of $500,-
000 of bonds, and on November 4, 1913, Multnomah County fol-
lowed suit by providing for an issue of bonds of $1,250,000.
The Acts provided that the work should be carried forward
by the regular County officers, except that in Oregon the Gov-
15
ernor of the State was to act with the County Commissioners for
certain purposes. The two Boards of County Commissioners
met in joint session November 29, 1913, and for convenience of
action organized themselves into the Columbia River Interstate
Bridge Commission, with Rufus C. Holman as permanent chair-
man, and with W. N. Marshall, auditor of Clarke County, as sec-
retary. A simple arrangement that all acts of the joint Commis-
sion would be ratified in due order by each separate Board made
it possible for the two Boards to act in unison. The personnel of
the Commission throughout the whole work is given on a pre-
ceding page.
The Commission took up as its first action the selection of
engineers for the work, and, after a month of investigation and
consideration, on December 29, 1913, your Engineers were chosen
from the dozen or more applicants. This prompt and timely
action in employing engineers had much to do with the success
of the work, for the Engineers found the Commission with open
minds, without preconceived ideas or set notions, and were able
to undertake the solution of the problems from a purely scien-
tific standpoint. The Commission directed the Engineers to pro-
ceed immediately with the necessary surveys and studies, and to
make a report recommending a location of the bridge over the
river and for an approach in Vancouver and one on the Port-
land side. After two and a half months spent in making sur-
veys, studies of traffic, estimates of cost, actively assisting in
securing options for rights-of-way for each location, and after
considering in every way four possible approaches on the Port-
land side and four in Vancouver, your Engineers reported their
findings and recommended locations on March 26, 1914. In order
to determine definitely the costs of right-of-way for each ap-
proach the Commissioners in Clarke County and Mr. J. Fred
Larson, acting for Multnomah County, had secured written
options on the lands required for all approaches at definite
prices. Definite and complete cost comparisons could thus be
made. After a few days of consideration, with public hearings
for citizens who wished to be heard concerning approaches, your
Commission adopted the Engineers' recommendations and fixed
the bridge approaches to be at Union Avenue on the Portland
side and at Washington Street on the Vancouver side, subject to
the conditions that the city of Porthind should extend Union
Avenue to the city limits and also should secure from the Port-
land Railway Light and Power Company an adequate release of
their exclusive rights over a certain strip of land which tliat com-
pany owned in the street, and to provide for "common user" over
16
the tracks of the company in that strip. The city of Portland
later fulfilled both of your conditions.
The Engineers had, in the meantime, been occupied with pre-
liminary borings and soundings for the several bridges. As soon
as the locations were fixed these investigations were pushed to
conclusion and preliminary plans for the bridges over the main
channel of the Columbia River, over Oregon Slough and over
Columbia Slough were prepared and copies were submitted to
the Secretary of War with applications for permits for construc-
tion. The customary public hearing before the Engineers of the
War Department was held in Portland on April 20th, and on June
12th, 1914 tentative approval of the plans was secured from the
Secretary of War. The preparation of final detailed plans and
specifications was immediately undertaken.
The Legal Department had been proceeding during the same
months and had taken the necessary steps by certain friendly
suits to establish the validity of the bond issues to such good pur-
pose that on July 14, 1914, the last necessary action was con-
cluded by a favorable decision of the Supreme Court of Oregon
relative to the Oregon bonds. The financial disturbance caused
by the beginning of the war in Europe in August, 1914, made it
impracticable to dispose of the bonds immediately, but in No-
vember each County satisfactorily placed a portion of its bonds,
and preliminary funds were secured. Upon advice of your Engi-
neers, however, that in the still unsettled condition of the money
market and the uneasiness of contractors in becoming largely
involved unless all funds were provided, the remaining bonds
were placed in December, 1914, so that the entire funds were on
hand to pay for the work. The correctness of the Commission's
action in this matter was thoroughly demonstrated when the bids
for the work were received, for they were unexpectedly and
agreeably low.
On January 11, 1915, the final detailed plans and specifica-
tions for the construction were submitted by the Engineers, were
approved and adopted by the Commission, and advertisements
for bids ordered. On February 23, 1915, bids were received from
twenty-four contractors. Acting on previous instructions from
your Commission, and as later described, your Engineers had
prepared complete plans for two different designs for the main
structure over the Columbia River channel, one containing a
movable span of the swing type, and the other one of the verti-
cal lift type. The lowest combination of bids received for each
design showed a saving by the use of the vertical lift type of
17
movable span, amounting to $70,013.60. On this showing, your
Commission on February 27, 1915, adopted the design contain-
ing that type and awarded contracts for the construction of the
bridges as follows :
Contract No. 1 — To the United States Steel Products Com-
pany, of San Francisco, for the manufacture of the superstruc-
ture metal work of the Columbia River bridge.
Contract No. 2 — To Porter Brothers, of Portland, for the
erection of the superstructure metal work of the Columbia
River bridge.
Contract No. 5 — To the Northwest Steel Company, of Port-
land, for the manufacture of the superstructure metal work of
the Oregon and Colmnbla Slough bridges.
Contract No. 6 — To Porter Brothers, of Portland, for the
erection of the superstructure metal work of the Oregon and
Columbia Slough bridges.
Contract No. 7 — To the Pacific Bridge Company, of Port-
land, for the foundations of the Columbia River bridge.
Contract No. 9 — To the Pacific Bridge Company, of Port-
land, for the foundations of the Oregon and Columbia Slough
bridges.
Contract No. 10 — To the Tacoma Dredging Company, of
Tacoma, Washington, for the approach embankments.
Contract No. 11 — ^To the Warren Construction Company,
of Portland, for the concrete deck slabs and paving on all the
steel bridges.
The bids received at this time for the paving of the embank-
ments were rejected owing to the small number of bids and the
feeling that those received were unduly high on account of the
length of time, about eighteen months, that must elapse before
work on this contract could be started.
The bids received on all of the contracts awarded at this
time were considerably lower than anticipated, so that there re-
mained sufficient funds from the proceeds of the bond Issues for
the construction of improvements not Included in the original
plans. The largest of these was the approach embankment to
the bridge from Derby Street, which serves a section of Portland
distant from Union Avenue, and for which there had been an
Insistent demand from the inception of the project. Your Engi-
neers submitted plans and specifications for the construction of
this approach embankment on April 2, 1915, at which time they
were approved by your Commission and the advertisement for
18
bids ordered. Bids were received on April 26, 1915, and on April
30, 1915, contract was awarded to the Standard American Dredg-
ing Company.
The awarding of the contract for the paving of embank-
ments was delayed partly from caution and partly by causes
beyond the control of your Commission or your Engineers.
Your Engineers deemed it advisable to wait until after the high
water of 1916 in order to observe the ctfects of such high water
on the embankments, and so as not unnecessarily to subject per-
manent pavement to possible settlements which might occur to
the new embankment with the first high water. This high water
occurred several weeks later than its expected time, was of more
than the ordinary height and of unusual duration. Moreover,
on account of questions relative to the granting of a franchise to
the Portland Railway Light and Power Company for the use of
the bridge, it was impossible to decide upon the extent of the
paving to be done on the embankments till late in the summer of
1916. On August 18, 1916, your Engineers submitted plans and
specifications governing the paving of all embankments, provid-
ing for the taking of bids upon various types in order to seciu-e
the fullest competition, and providing also for various widths of
pavement pending the settlement of franchise matters over the
approaches and the decision of your Commission as to the paved
width to be provided. Bids were received on September 19,
1916, and agreement having been reached meanwhile with the
Portland Railway, Light and Power Company, whereby it would
use the Columbia River bridge and Vancouver approach, but not
the Union Avenue approach, your Commission decided to pave
a 38-ft. width over Hayden Island, 30 ft. on the Union Avenue
approach south of Oregon Slough and 18 ft. on the Derby
Street approach. Contract was awarded on September 20, 1916,
to the Warren Construction Company for bitulithic pavement
on broken stone base for Union Avenue approach, macadam for
Derby Street approach and bitulithic pavement in Vancouver.
The awarding of this contract provided for the last item of
construction with the exception of the lighting system. Con-
tracts for the furnishing of the main items of material for this
system were awarded on October 27, 1916, to the United States
Steel Products Company and the Pacific States Electric Com-
pany, and on March 6, 1917, contract for the installation of the
lighting system was awarded to Nelson & Brown.
The various contractors assembled materials and equipment
immediately after the signing of their respective contracts, and
construction proceeded as rapidly as the river conditions would
permit. Although practically all of the contractors were work-
ing at the same time, the whole work progressed smoothly and
substantially without friction or interference under the capable
and efficient supervision of the Engineers' representative in
charge, Mr. Frank M. Cortelyou, Resident Engineer.
Following the signing of the contracts, your Commission was
occupied with the final acquirement of the lands for right-of-
way, with consideration through committees of franchises and
of matters relating to management of the property after the con-
struction should be finished, with the determination of the in-
come required for proper operation and of toll charges neces-
sary to provide it. Mr. Evans concluded that certain special leg-
islation was desirable in Oregon to simplify the control of the
property and the passage of suitable bills by the Legislature of
the State was secured. The Commission met from time to time
to receive reports of progress from the Engineers and to approve
for payment the monthly payment estimates to the contractors
for the work done. The public necessities made it appear desir-
20
able to the Commission to provide for traffic at the earliest date
possible, and the bridge was opened to traffic as soon as the
pavement of the roadways had been completed, and several
weeks before the last of the work, comprising the finishing
touches to the structure, had been carried out.
The following pages include a general description of the bridge
and approaches, and information concerning the loadings for
which the bridge is designed; a description of some of the inter-
esting construction features, a tabulation of the quantities in the
structure and of the costs and classification of costs; a summary
of the franchise provisions of the Portland Railway, Light and
Power Company; and, finally, suggestions for maintenance and
operation of the structure, which should come to the attention of
the Commission.
GENERAL DESCRIPTION OF BRIDGE
The Columbia River Interstate Bridge and Approaches ex-
tends across the valley of the Columbia River from the city lim-
its of Vancouver, Washington, to the city limits of Portland,
Oregon, a distance of three and a quarter miles, and includes
about 5,000 lineal ft. of steel bridge structures and 12,000 ft.
of embankment, in addition to which there is a secondary em-
bankment on the Oregon side about 6,000 ft. long. The bridge
and approaches provide a roadway for street traffic and tracks
for street cars, and over steel structures a sidewalk. At times of
extreme flood, the high water covers the entire three-mile width
of valley and extends from Vancouver to the city limits of Port-
land.
The Columbia River at the bridge site is 3,500 ft, wide, with
a maximum depth of 30 ft. at extreme low water and with vari-
ation from extreme low to extreme high water of 33 ft. The
water rises each spring to about 20 ft. and about once in four
years to 25 ft. So far as known it has reached 33 ft. only once.
The bed of the river consists of sand, with small amounts of
gravel, extending to great depths. At the north shore very com-
pact cemented gravel is found a few feet below low water, drop-
ping off to 100 ft. below at about 700 ft. from the north shore.
Over the remainder of the river only sand with some gravel was
found to depths of more than 100 ft.
The Oregon Slough forms an important secondary channel,
particularly for flood conditions. It is about 1,000 ft. wide, and
21
25 ft. deep, and is separated from the main river by an island
about 1,500 ft. wide. The U. S. Government has built a dyke
some distance above the bridge site and the island to divert prac-
tically all of the low water flow down the main channel of the
river, the top of the dike being about 6 ft. above low water. The
bed of this slough is principally sand. The Columbia Slough
provides some drainage near the Oregon side of the valley, is
about 300 ft. wide and 20 ft. deep at low water. The bottom is
of very soft clay and sand; hard and compact gravel is found
about 80 ft. below low water. The average elevation of the
ground across the river valley is from 12 to 15 ft. above low
water, so that much of it is inundated at every high water
period.
The roadway is 38 ft. wide between curbs on the steel spans,
38 ft. wide between rock shoulders across Hayden Island, 30 ft.
wide on the balance of the Union Avenue approach and 18 ft.
wide on the Derby Street approach. Over the steel spans there
is one sidewalk 5 ft. wide. Double track street car tracks for
both standard and narrow gauges are placed in the middle of
the roadway on the steel structure, spaced 10 ft. 8V2 ins. center
to center. The vertical clearance on the truss spans is 21 ft. 6
ins. The roadway on the steel structures across Hayden Island
and on the Union Avenue approach is paved with bitulithic
pavement and on the Derby Street approach with macadam.
The bridge over the Columbia River consists of a series of
through riveted truss spans with curved top chords; three spans
275 ft. long and ten spans 265 ft. long, together with a small deck
girder span at the Vancouver end, making a total length of 3,531
ft. 5y8 ins. between end shoes. Provision for navigation on the
river is made by a vertical lift span. The central of three 275
ft. spans is arranged to lift between towers on the other two, so
as to afford a channel 250 ft. wide at right angles to the current
of the river and 150 ft. high above ordinary high water.
For the through spans the trusses are spaced 41 ft. center
to center, with the roadway between and the sidewalk beyond
one truss. The floor is a reinforced concrete slah 5Vi ins. thick,
and the sidewalk is also of reinforced concrete. The arrange-
ment of the beams and of the concrete slab for the floor merits
attention, as it is new and original. Between usual floor beams
are longitudinal stringers spaced about 9 ft. center to center. On
top of the stringers, extending entirely across the roadway, there
are 8 ins. I beams spaced about 33 ins. apart. These roadway
cross beams are bent to conform to the crown of the roadway,
and the concrete slab rests immediately on top of them. The six
22
rails required for the two-gauge, double-track, street car tracks
rest immediately upon the roadway cross floor beams and are
fastened to them by standard Carnegie steel tie clips. The rails
are 7 ins. high, so that there remains a space of 2 ins. in depth
above the top of the concrete slabs to the top of the rail for the 2
ins. bitulithic surfacing which forms the pavement. To afford a
rail heading which could be removed, if necessary, for access to
the rails, or to the bonding, without injury to the roadway slab,
the space about 5 ins. wide, on each side of each rail, is filled with
concrete to the top of the rails, a flangeway being provided by
forming this concrete. A drainage intake with down-spout is
placed at intervals of fifty feet along each curb.
JS^CyetTT JfbcKAt€r/
P S-^'' ^A9'-< - --- ^■
' ' — . .. ^--,- ,.^^. , 2''Bifufifhic\PcTvement J .^^^^
fA*iiif^f^^
jL
Section A-B
- — II
'■'WW
T
a'
~a^-- >4
-4-1 'C. to C. of Trusses
EnfU- News.
This arrangement of floor has the advantage of providing a
concrete slab longitudinal in the direction of travel, with com-
paratively short spans, and of making the supporting steel beams
of very simple shop work. Owing to the lateral stiffness of the
floor as constructed, the lower laterals of the spans are somewhat
lighter than they would be for an open deck bridge.
Two fixed ends and two expansion ends of the spans are
placed adjacent so as to reduce the number of expansion joints
to a minimum. The expansion joints are made of usual type
checkered plates supported by and sliding upon metal supports.
The corresponding expansion joints for the rails between the
spans consists of manganese-steel castings placed beside the
webs of the rails, for which one side of the rail heads is planed
off.
The towers supporting the lift span are of simple construc-
tion, riveted throughout, so arranged that the front columns of
the towers support all the loads of the lift span and counter-
weights. The rear columns are bracing members. The lift span
23
is suspended from each of its four corners by sixteen plow steel
wire ropes, 2 ins. diameter, which pass up and over cast steel
sheaves 12 ft. in diameter, and are attached by a group of
equalizing levers to concrete counterweights built around steel
frames. These counterweights are of the same weight as the
span, as nearly as possible exactly to balance it, so that thC'
work to be done in operation consists of overcoming the friction
and inertia, and of lifting the unbalanced portion of the ropes.
The span is guided in its ascent and descent by cast steel jaws
which engage upon tracks on the towers; at one end of the lift
MANUFACTURING THE STEUL.
The machinery tor operating the lift spun is here seen assembled eoinplete In the
sbop where It whs made, and placed on the structural members. This xias done to Insure
accurate fitting ot the parts. The slmpUclly of the operating machinery is npparent.
Span these jaws guide both laterally and longitudinally, but
at the other end llie span is guided only laterally, thus allowing
for expansion and contraction of the span and for slight varia-
tion in position of the towers. Operation is eflfected by means
of operating ropes, of which there are two pairs at each comer
of the span. The operating machinery, which is placed upon the
span at its center, just above the roadway clearance, consists of
four spirally grooved drums connected by a train of gears to an
electric motor. Each of these drmns controls the operating
ropes for one corner of the span; one pair of operating ropes,
leading from the top of the drum, passes over a deflecting sheave
at the corner of the span, thence downward, and connects near
the bottom of the tower; and a corresponding pair of operating
ropes leading from the bottom of the drum passes under a de-
flecting sheave at the corner of the span, thence upward, and
connects near the top of the tower. All of the drums are sim-
ilarly connected so that when they are operated in one direction
the ropes leading to the tops of tlie towers are wound on the
drums, and those leading to the bottoms of the towers are payed
off, lifting the span by the force exerted upon the corner sheaves.
The machinery for operation is thus exceedingly simple, consist-
ing of one transverse shaft extending across the span; one pair
of reduction gears in a frame inside of the house, and the back
gears upon the motor. An indicator and limit switch is provided
by which the current is automatically cut off and solenoid brakes
applied to the motors at near the upper and near the lower
limit of the run of the span. For ordinary operation there is a
hand band-brake, which is equipped with a push button switch,
so that when the span is under control the operator can hold off
the emergency brake, and bring the span to rest in the control of
the hand brake.
To provide for emergency operation, instead of the usual
hand operating capstan, the span is equipped with a 12-horse-
power gasoline engine connected through a speed reducer to the
machinery, so that in case of failure of electric current the oper-
ator will be able to move the span at slow speed without having
to seek outside assistance. There is a manually operated lock
at each end of the span in connection with a centering device so
that the span may be locked down. The solenoid brakes in con-
nection with the down haul ropes also serve as a lock. Buss-
bar trolleys are attached to one tow^er and a sliding contact shoe
on the lift span supplies the current to the motors during oper-
ation. The operating ropes are attached at the tops of the
towers to small drums with worm gear connections so that ad-
justment for the stretch of the operating ropes can readily be
made. When the span is at its upper limit the counterweights
are two feet above the floor level and a special arrangement of
the trolley wires under the counterweight is made. This con-
sists of swinging frames upon which the trolley wires are
fastened, and which arc pushed down by the counterweights and
25
returned to position througli means of small counter-balances.
The rail connections at the ends of the movable span are simple
sciirfed joints so that the span lifts away from the fixed rails
and returns to them without any movable devices. The ma-
chinery is designed with great care and nicety. Gears and
pinions which operate together are set in cast steel frames so
that they could be adjusted and built complete in the shops; the
adjustment of parts of the machinery in the field being reduced
span weighs Hljout
iiovlng
to 136
to a minimum. All of the gears arc cast steel with cut teeth.
There is duplicate motor equipment with either motor of suf-
ficient size to operate the bridge.
At the ends of the fixed spans adjacent to the movable span
there are provided roadway gates of substantial design to make
an elTecfivc barrier across the roadway, and these are connected
to derailing switches in the street car tracks so that when the
gate is closed across the roadway, the derail is thrown. These
gates are manually operated and a small steel and concrete cabin
is provided at each for the gate tender.
Several types of movable spans to provide the necessary
channel openings for river navigation were considered, and the
matter was narrowed to the selection of either a swing span or a
vertical lift span. The Commissioners then desired to receive
bids both upon the lift span and the swing span, and plans were
prepared for the structure containing both types of movable
span. The designs were made according to the same specifica-
tions and as nearly duplicate in character as possible.
Application was made to the War Department and tentative
approval was received for either type of movable span, provided
the swing span should have two channels, 200 ft. wide, or the
lift span should provide one channel 250 ft. wide, with a vertical
clearance of 150 ft. above normal high water. As has been
stated, bids were received on both types of structure and it de-
veloped that the lowest bid for the bridge, including a lift span,
was about $70,000 less than the lowest bid for the bridge, includ-
ing a swing span. The lift span was thereupon adopted; not
only for the advantage of the lower first cost, but also because,
judging from the experiences of Multnomah County in operating
bridges of both types, there will be continued advantages in
lower cost of operation and maintenance. It is likewise more
advantageous for river navigation, in that it provides a channel
250 ft. wide instead of 200 ft. wide, and the channel is not ham-
pered by the long draw protection that would be necessary with
a swing span. As the main channel is very close to the Van-
couver shore, the necessary draw protection, about 500 ft. long,
would have been a serious detriment to the dock frontage ad-
jacent to the bridge.
The river at the site of the bridge is subject to a certain
amount of scour, but inspection of the soundings taken for many
years past did not disclose any indication of scour to extreme or
unusual depths, although the river, both for some distance up
stream and some three miles down stream, is deeper than at this
site. The bases of the piers are of concrete enclosed by heavj'^
timber cribs and extend down from 20 to 25 ft. below the river
bed. The bases rest upon piles which extend to a depth about
110 ft. below low water. The piles used were about 120 ft. long
in single sticks, about 10 ins. diameter at the tip and about 22
ins. at the butt. There is an average of about one pile to ten
square feet area of base and in the average pier under the 265
ft. spans there are ninety piles.
27
K 4i'ChC of Trusses -
Crown ofHeac/Kov. fiMAOS
I 111
The foundation
piles are cut off a few
feet below low water
so that the upper ends
of these piles arc im-
hedded into the con-
crete of the bases of
the piers from 15 to
20 ft. and the piles
form a definite por-
tion of the pier. It is
evident that even
though some unusual^
scour should, on some
extraordinary occas-
ion, extend below the
bottom of the base,
the pier would still be
perfectly stable, ow-
ing to the great depth
of penetration of the
piles and to the rigid-
ity of their upper sup-
port. Around each
pier base there is an
amount of heavy
stone rip-rapping, ^^^.'/-^ ,5^^-^
which should be re- Boso t*lan of Wer 4. *^'«'- "***
plcnished, if necessary, during the next few years.
The shafts of the piers above the base are comprised of two
cylindrical battered columns, one placed under each pair of
shoes. These columns are joined by a vertical diaphragm and
by the horizontal coping at the top, both of which are reinforced
with steel. This design saves considerable weight which other-
wise would require supporting piles and eliminates a large
amount of concrete unnecessary for any structural purpose.
The occurrence of ice in the Columbia River in sheets or
floes of large size is very rare, so that the concrete piers need no
special protection of steel or stone facing.
The bridges over the sloughs consist of deck spans providing
a roadway and floor of the same type and character as previous-
ly described, except that the girders are placed 23 ft. apart
< ^' i^Vx- '
11
H!i-
W§M
28
transversely and a portion of the roadway and the sidewalk is
carried oH cantilever beams^ and there are other minor details
of differences, such as necessary trolley poles, etc. These spans
rest on concrete piers supported by piles of the same general
type as described, for the main river. The piles were sunk to
about the same depths, but as the likelihood of scour is much
less in the sloughs, the bases are not carried as far below the
river bed.
The bridge over the Oregon Slough consists of ten deck
girder spans 100 ft. long, and one span 115 ft. long, making the
total length 1,137 ft. 6 ins. At the present time there is no navi-
gation in the Oregon Slough above the site of the bridge, but as
there is possibility of navigation being developed above the site,
it was necessary to provide for some type of movable span to
furnish the necessary channel openings for vessels. Permission
was secured from the War Department to build the structure
with all fixed spans at the present time, with the provision that
one span should be so arranged that at any time in the future
when it may become necessary it can be converted into a mov-
able span by providing towers at each end, and by equipping it
with machinery, counterweights, etc., so that it may be operated
as a vertical lift span. The 115 ft. span, above mentioned, is
arranged for such possible use and will aflford a channel 100 ft.
wide. This provision and arrangement saves the Commission an
expenditure at the present time of about $30,000 and permits a
movable span to be provided when necessary without discarding
any parts of the present structure and without interrupting
traffic.
The bridge over the Columbia Slough consists of four deck
girder spans of the same general type as described for the Ore-
gon Slough, each 75 ft. long. After the first tentative approval
of the plan for the Columbia Slough bridge was given by the
engineers of the War Department, the status of this slough was
changed so that there has become a remote possibility that it
may at some time be considered navigable. It has therefore
been agreed that should such development occur, one of these
75 ft. spans will be made to lift in the same manner as above de-
scribed, providing a clear channel opening of 60 ft. in width.
The embankment over Hayden Island has a total length of
about 1,480 ft., the embankment of the main approach to Union
Avenue has a total length of about 10,500 ft., and the embank-
ment in the secondary approach to Derby Street has a total
length of about 5,800 ft. The embankment for the tw^o ap-
proaches in Vancouver has a total length of about 500 ft.
29
The embankments across Haydcn Island and in (he main
approach to Union Avenue are 42 ft. wide on top. The embank-
ment of the secondary approach to Derby Street is 40 ft. wide on
top and on the Vancouver approaches the widths conform to the
widths of the streets occupied. The embankments average about
24 ft. in height and have side slopes of 2 horizontal to 1 vertical.
The upstream side of the Union Avenue embankment is pro-
tected to (he elevation of 20 ft. above low water by concrete
slabs laid on the slope of the finished fill. These slabs are 4 ins.
thick, reinforced with wire mesh and in strips about 8 ft. wide,
extending continuously up and down the slope. The overflow
EMBANKMENT CONSTRUCTION,
Union Avenue uppronch embankment. In the distance tlie completed cinbankntcnt
can l» sron: nenr at linnd tlie sand Is Just beginning to be deposited between tlie lowest
bulkheads. Tiie sand wus pumped through 24-1n. pipe, a maxiniuni distnnce oF 1% miles.
water, which at limes of high water inundates most of the river
valley, is largely back water and has no perceptible current, ex-
cept that caused by its outflow from the river over the land as
the river rises and its return flow to the river as the river falls.
The time of greatest current with corresponding danger of
erosion is at the time when the water is slightly above (he height
of the river bank, and occurs near the banks. For this reason
the concrete protection has been carried up to an elevation of 30
ft. above low water at the ends of the embankment where the
high water of 1916 indicated erosion would occur, and at the
buried piers has been carried up the full height of the embank-
ment. The area on the slopes not covered by the slabs has been
heavily fertilized and sown to grass, and it is expected that com-
pact sod will be secured which will prevent local erosion. Great
numbers of evergreen blackberries, a hardy indigenous shrub,
have also been set out on the slopes to help in the prevention of
erosion. The railing along each side of the embankment is of
timber throughout of ample strength and rigidity for the pre-
vention of serious accidents, as has already been proved.
The embankment across Hayden Island is more exposed
than the other embankment and the Engineers of the War De-
partment required that the slope protection extend entirely
over both sides up to an elevation 30 ft. above low water or 5 ft.
above normal high water. Owing to the exposed position of the
Vancouver embankment, the slope protection there was similarly
carried up to an elevation 30 ft. above low water.
On the Derby Street approach the high water of 1916 indi-
cated that there was no serious danger of erosion from current
except at the ends of the embankment. The Union Avenue ap-
proach serves as a protection to the major part of the upstream
slope of this embankment, so that the concrete slope protection
was provided only at its ends.
At each end of the main river bridge there are two entrance
columns or pylons of concrete. These are of concrete rather
than cut stone or marble because they more fitly represent the
simple, straightforward construction of the bridge. They bear
bronze tablets which give not only the names of the Commis-
sioners, of the Engineers and of the Contractors, but also certain
inscriptions which seemed to your Engineers to represent some-
thing of the thought and purpose and ideals of those respon-
sible for the bridge. The inscription from Macaulay seems
fitly to represent the purpose of the bridge; the inscription from
Ruskin may fairly give the spirit of the builders, your Con-
tractors and your Engineers; that from Carl Schurz is an appeal
for remembrance of old ideals of patriotism and of service not
unsymbolized by the bridge; and the last from the pen of Rich-
ard W. Montague and your Engineers is believed truly to indi-
cate the origin and purpose of the whole endeavor.
By permission of the Commission, the Washington chap-
ters of D. A. R. and S. A. R. have erected at the Vancouver end
31
of the bridge as a marker for the old Oregon Trail a simple stone
drinking fountain which bears a bronze tablet symbolic of the
Spirit of the Trail. The Oregon chapter of the same organiza-
tion applied for and received similar permission for the erection
of the trail marker at the Oregon end of the bridge.
Along both sides of the Union Avenue approach there have
been planted roses and Scotch broom and there is similar plant-
ing about the entrance columns (seventeen hundred rose bushes
and thirty-five hundred Scotch broom plants were set out) . With
a small amount of care and attention there will soon be added
beauty to the substantial utility of the approach embankments.
LOADS FOR WHICH THE BRIDGE IS DESIGNED
The attention of your Conunission is particularly called to
the loads for which the steel portions of the structure were
designed. In addition to the actual calculated dead load weight
of all parts, and wind loads, provision was made for the follow-
ing live, or moving, Ipads :
For the floor system and for girders :
On Street Car Tracks — Two 50-ton cars on each track.
On Roadways — 12-ton motor truck, with special provisions
for 24-ton machinery truck or loads per linear foot for
each line of traffic varying with loaded length from 812
pounds for 25 feet to 735 pounds for 100 feet.
On Sidewalk — 600 pounds per linear foot.
Impact allowance of 50 per cent is added to all except side-
walk loads.
For trusses:
On Street Car Tracks — Two 40-ton cars on each track.
On Roadways — Loads per linear foot for each line of traffic
of about 500 pounds, but varying with the loaded length.
For impact allowances the following percentage of each load
is added to it:
For roadway loading— I = nlTsoo ^^* "^* greater than fifty
per cent.
For street car loading — I = ^j^^-^^^^ not greater than fifty
per cent.
32
Where I = percentage.
L = Length of load on bridge producing maximum
stress.
N = Number of loaded tracks for street car loading,
or number of lines of traffic for highway load-
ing.
The above figures will convey to an engineer the permissible
loads to be allowed to cross the bridge, but a more detailed state-
ment may be of service to the Commission. The bridge was not
designed for heavy locomotives or heavy railroad trains. Light
trains, of course, can be operated across it with safety. The
following limitation, which is included in your franchise to the
only railway company now operating, sets out the maximum
weights of locomotives, cars and trains which should be per-
mitted to operate across the bridge. This should be your guide
for granting permission for operation of trains or cars on the
bridge :
"No car or locomotive of any character weighing in excess
of 100,000 pounds gross load, or having any single axle load in
excess of 25,000 pounds, shall be permitted on the structure; and
no cars weighing over 80,000 pounds having a length of less than
20 ft. c. to c. of trucks shall be permitted on the structure. Two
coupled locomotives or cars shall not weigh in excess of 180,000
pounds gross load; three coupled locomotives or cars shall
weigh not in excess of 190,000 pounds gross load nor more than
1,600 pounds per lineal foot; four coupled cars or locomotives
shall weigh not in excess of 210,000 pounds, nor more than 1,300
pounds per lineal foot; five coupled locomotives or cars shall
weigh not in excess of 230,000 pounds, nor more than 1,200
pounds per lineal foot. Trains composed of more than five loco-
motives or cars, or both, shall weigh not more than 1,100 pounds
per lineal foot."
The limitation on the roadway of a truck with load totaling
24 tons as given above needs no special explanation. The speci-
fications for design employed have not been published and space
does not permit their inclusion here, but if the Commission
should at any time need information concerning unit stresses
and details of design your Engineers will make a supplementary
report to give that information.
33
SPECIAL FEATURES OF DESIGN
The marked economy of design came from a thorough study
of local conditions and local possibilities for materials, and a
fitting of the design and the plans to realize every possible ad-
vantage so offered. Possibly nowhere in the world are extreme-
ly long timber piles available at as low a price as at this bridge
nif-arivcr equipmcni usea lo Sinn me lounauiion piies i
piers. The leads are 122 ft. high obove the water; the overh
22 H. in front of iMirgc. Equipped wllh two liobtltis engine
pumps, and SOO-H.P. boiler.
site. Not only the river bed conditions already described, but
this exceptional facility for securing such piles at reasonable
cost was a considerable factor in delemiining upon the exact
type of piers to be used. As has been described, the piles as de-
livered were single sticks from 120 ft. to 125 ft, long. The
speciiications described the special equipment, which would be
34
required for sinking these piles, an equipment which proved to
be adequate and which accomplished the work, so that the piers
as they stand are on piles which on the average extend into the
river bed 25 ft. deeper than the bottoms of the piers of the
railroad bridge adjacent. The conditions of the Columbia River
and of the Oregon Slough were deemed to be particularly favor-
able to the erection of practically the entire bridge by building
the spans on shore and floating them to position. The plans
were made with this in view and the specifications indicated a
preference for this method of construction, although the ordinary
method of driving piles and building a temporary trestle on
which to erect the steel work was not debarred. Different con-
tractors bid upon different methods, but the bid taking advan-
tage of the opportunity for floating the spans into place was
$50,000 lower than the lowest bid for erecting on falsework. The
exceptional opportunities for constructing the approaches by
building permanent embankments by the hydraulic filling
process also seemed to your Engineers to fix this as the proper
design of structure, for there were abundant supplies of sand in
Oregon Slough; cheap electric power, little difficulty with dis-
posal of excess water, and cheap lumber for bulkheads; and the
specifications so provided for dredging, although no limitation
was made on the construction of the embankments by steam
shovel and train haul, or other methods. Even though the
length of embankment was beyond any precedent for this kind
of work that your Engineers could find, the correctness of this
decision was also verified when the bids for placing the work by
hydraulic dredging were found to be less than two-thirds of the
lowest bid contemplating train haul.
In the preparation of the plans, minute care was taken to
secure every possible advantage which a duplication of items
would afford. In the steel work there are, over the Columbia
River, only two different truss spans, and the floor systems even
of these are duplicated. Over the Oregon Slough there are like-
wise two patterns of longitudinal girders with one pattern of
floor system, and over the Columbia Slough the girders are all
duplicates and the floor system is the same as on the Oregon
Slough. It was, therefore, possible for the structural shops to
make only a few sets of patterns and to duplicate the parts many
times, and this contributed very materially to the low price for
manufactured steel. The same duplication was followed as far
as possible in the design of the substructure so that the coffer-
dams and forms for the concrete could be moved from one pier
to another and used repeatedly. The concrete floor was designed
35
so that the forms would be duplicate and interchangeable, and
these were used repeatedly.
The details of every part were simplified with the most care-
ful attention so as to make the manufacture and fabrication
with as little complexity as possible, with the result that the
steel work as delivered, both from the shops of the American
Bridge Company and the Northwest Steel Company, was in ex-
cellent condition to he readily erected, properly fitting in every
part. So accurately was the work of the American Bridge Com-
pany for the Columbia River trusses carried out that in driving
the 17.000 field rivets in the first truss span there were found
MANUFACTURING THE STEEL.
View tnkcD at fiary. III. All of the trusses were assembled at
lying on the ground here, all the holes for field rivets reanipd, and II
match marked so they could be erected In Vancouver In Just the ai
insured pprlect matching of holes for the Held rivets.
imc posit
only six rivet holes which had to be corrected in any way for
the entrance of the rivet, and other spans were of the same gen-
eral character. The same care of detailing and duplication of
parts will be found in the machinery for operating the lift span
and even in such details as the framing of timbers for the bases
of the piers. The concrete floor slab was placed in just the posi-
tion so that the reinforcing bars could be laid down on the steel
cross beams and need no other support.
:)fi
CONSTRUCTION METHODS AND EXPERIENCES
A complete description of the processes of construction will
not be attempted, but three features which were of special in-
terest deserve some description. These are (1) the method of
building the piers and placing the long piles already described;
(2) the erection of the superstructure metalwork by building the
spans on shore complete and floating them to the piers; and (3)
the construction of the approach embankments by hydraulic
dredging.
(1) The plant and equipment supplied by the Pacific Bridge
Company were unusual in certain respects and peculiarly
adapted to the work in hand. Excavation was made by a dipper
BUILDING THE PIERS.
c pier had been t
RemovlDg a wooden colTrrdBin Ifl ft. wide. 57 fl. toDR and 17 ft. hlKli weighliig SO
_. . .._.. „.... .u- , ., r .u _.- _,._ ^.j ■-- iilullt Inside IL
This colTerdniD was used for one pier after aiioi
dredge of the shovel type having a 4 cubic yard bucket, an un-
usual equipment for such work. With this machine a hole was
dredged into the river bed at the site of the pier to the full
depth required and large enough to let the sides of the excava-
tion take a natural slope. The timber crib enclosing the base
of the pier was partly built on launching ways, floated to posi-
tion and framed up to full height. A removable cofferdam in
one section, used successively on diflf erent piers, was then picked
up and placed on the crib, the crib sunk to the proper depth in
37
the excavation, and material of the river bed banked around
outside to hoTd it in position. The foundation piles were then
sunk by water jets inside of the crib.
For the sinking of these piles in the piers the second excep-
tional piece of equipment was provided, consisting of a pile
driver of which the leads were 122 ft. high above the water, and
built so as to overhang in front of the barge upon which it was
supported about 22 ft. The lowest portion of this overhanging
part was about 15 ft. above the water, so that this overhang
made it possible to drive all of the piles in a pier from one side
of the crib and at any stage of the water. This pile driver was
mounted on a wooden scow 32 by 100 ft., 7 ft. deep. In addition
to a No. 2 Vulcan Steam Hammer, the driver was equipped with
two 4 ins. diameter jet pipes, 110 ft. long, connected by flexible
hoses to the pumps. Water was supplied to the jets by two 12
ins. X 18 ins. x 10 ins. compound duplex pumps, each having
a capacity of 1,000 gallons per minute. One four-drum hoisting
engine and one two-drum hoisting engine supplied the power
for handling the equipment and were all furnished steam from
an 800-horsepower boiler. A pile would be set in place on the
river bed and the jets discharging water with nozzle pressure
of from 100 to 150 pounds per square inch played at its point.
The jets thus bored a hole into which the pile slid down with
the help of the steam hammer. It was an ordinary experience
for one of these long piles to be sunk entirely to place within
ten minutes after being placed in the leads and as many as 25
piles were driven in one day.
After the piles had been driven, the sand, gravel and other
material washed up inside the crib by the driving was removed
down to the bottom of the base and the base was filled by de-
positing concrete under water, through a tremie, up to within
a couple of feet of the pile cut-off. When this concrete had
thoroughly set the crib was pumped out, the piles sawed off and
the remainder of the concrete for the base placed in the open.
Wooden forms for the shafts of the piers of usual character were
then built up to above water level and filled with concrete. The
one-section cofferdam was then lifted off, to be used on a suc-
ceeding pier, and the remainder of the shaft forms built up and
concreted. The river bed surrounding the pier could then be
properly leveled up and adequate amounts of large rip-rap
stone placed about the pier. This difficult foundation work was
carried out by Mr. C. F. Swigert of Portland, under his personal
direction.
38
(2) For the erection of the superstructure metal work of the
Columbia River Bridge the Contractor arranged a material and
erection yard in Vancouver. Each span was erected parallel to
the river on low falsework well back on the bank of the river.
Launching ways were built at right angles to the erection false-
work and extended from it out into the river into deep water
at about the same height as the piers. These were 270 ft. long
MG THE SUPERSTRUCTURE METALWORK,
The spans were erected back on shore, to the left, and b» ■■nrh ivoi
riveted it was rolled out over the wolt-r on Ihe ways. The s
traeks, the launching ways and five nearly completed spans are seen.
and each consisted of a heavy trestle with bents of piles spaced
5 ft. centers of five piles each with suitable caps. On each
were four timber stringers 10 ins. by 20 ins. and on top of the
stringers eight lines of 2V2 ins. steel rails. Each span was
erected by derrick cars operating on tracks running along each
side of the falsework, and after all of the steel was in place and
ail of the rivets driven, the span was rolled out on the launch-
ing ways, using 22 rollers V/2 ins, diameter under each corner.
Successive spans were thus built on the same falsework and
rolled out on the same launching ways.
For moving the spans from the launching ways to the piers,
four harges were used, on which falsework of tlmhers was built
up to a proper height so that with a span on the barges the shoe
of the span would be a few inches above the tops of the piers.
When ready for moving, water was pumped into the scows sup-
porting the falsework and they were floated underneath the span
between the launching ways. Blocking was then placed between
the falsework on the scows and the under part of the span so as
to provide proper bearing, and the water pumped out of the
scows, so lifting the span off the ways. The span floating on
the barges was then towed out to position over the piers by
One of the bnrgps for carrying the spiin may be :
steamboats and tugs and water was pumped into the scows,
lowering them and bringing the span to rest on the piers, and
finally entirely releasing the scows, which were then taken back
for another span.
The erection of the towers and other portions of the structure
were by methods not unusual in steel erection, except that for
the Oregon and Columbia Slough spans the material was all
floated near to position on scows and erected from them. The
economies afforded by this method of erection have already
been mentioned. The work was carried out under the personal
direction of Mr. Guy Willard.
(3) The Tacoma Dredging Company moved its hydraulic
dredge to the bridge site, installed pipes and pumped its first
sand on June 9, 1915. By November 20th of the same year all
of the embankment of the Union Avenue approach south of
Oregon Slough had been placed, so that the placing of this ma-
terial, which had a total net volume of 821,000 cubic yards, occu-
pied 160 days, or a net average of about 5,000 cubic yards a day.
ERECTING THE SUPEUSTKUCTURE METALWORK.
launching ways on shore
Tniiisporling one at Uie xpaiis frnm the |.
aoatina. The span Is 273 ft. long and weighs
above the water. Four barges and two steaniboi
The material was excavated from the Oregon Slough by
means of a suction dredge with a cutting head and was trans-
ported to place by being pumped through a line of pipe 24 ins.
in diameter. The operation was by electric power and the main
pump on the dredge was operated by two 500-horsepower
motors. The pump was of capacity to give a discharge through
the 24-inch pipe at a velocity of 12 lo 15 feet per second. Oper-
ation continued 24 hours per day during the time specified and
the dredge was actually running about 14 hours per day. For
periods of a few hours at a time the dredge pumped as much as
1,000 cubic yards per hour. There was, of course, a very con-
siderable run-off of sand from the embankment, as well as a
certain amount of fine material which flowed away with the
waste water, and it is estimated that about 250,000 cubic yards
more than the above net amount was transported. The dis-
charge pipe line was extended to a length of about 5,500 ft.,
working from the dredge alone. For the greater distances a
booster pump was installed in the line to give additional impetus.
This pump was operated by a single 1,000-horsepower motor
operating with considerable overload. The dredge and booster
pump together transported through a maximum length of 9,000
ft. of pipe. Such long distance dredging into an embankment so
comparatively narrow and high is believed to mark a record for
work of this character. The pipe was of the ordinary riveted
variety with slip joints made of 7 gauge material on the pon-
toons and of 10 gauge material elsewhere. It was moved about
by teams and wagons.
The embankment was formed by the use of timber bulk-
heads. These were built of 6 by 8 ins. posts, about 10 ft. centers,
supporting 2 by 12 ins. sheathing, surfaced both edges. The sides
of the embankment were built up by these means in steps 8 ft.
wide and 4 ft. high. The first bulkheads were placed upon the
natural ground surface by driving in the 6 by 8 ins. posts with
a hand maul and setting the lower plank into a small trench so
that the bulkhead sheathing extended perhaps 8 to 12 ins. below
the ordinary ground surface. When the sand had been filled in
about the top of such first bulkheads, posts for succeeding bulk-
heads were set in place and the lower plank placed so that it ex-
tended about 12 ins. below the top of the first bulkhead below.
These posts were tied back into the embankment by 2 by 6 ins.
ties spiked on near the top of each post and extending back to a
short post, in front of which were placed a few pieces of lagging
to offer additional resistance. The pipe was laid to discharge
into the middle of the embankment and was carried forward
from the river, bringing the embankment up to the final grade
and working away from the dredge. A framework of baffle-
boards was placed under the discharging end of the pipe, caus-
ing the water to spread out and spill over the ground below and
run forward, distributing the different sizes of material as the
velocity decreased. At some convenient low point there was pro-
vided an outflow down the side of the embankment, for which
the steps of the embankment were paved with plank to prevent
wash.
42
The methods of constructing the bulkheads and of the dis-
charge arrangement are clearly shown by the accompanying
photographs. After sections of the finished embankments be-
came thoroughly drained as the work proceeded, the posts of the
bulkheads were cut away and the planks removed and carried
forward for repeated use. Parts of the posts and of the 2 by 6
ins. ties therefore remain in the embankment. The finishing of
the slopes was done by hand with shovels, and the successive
steps were so located that the upper corner of each step filled
into the lower corner of the step below, to provide the proper
slope. The actual pumping and transportation of the sand in
EMBANKMENT CONSTRUCTION.
Near view ot Union Avenue approach embankment while depositing sand by pump-
ina through S-l-in. pipe. The wooden bulkheads were removed after pumping was
finished, and the embankment dressed to smooth slopes.
the hands of these Contractors were the simplest parts of the
work, and they found it economical to permit a very consider-
able wastage of material where such wastage saved in the con-
struction of bulkheads.
This work was carried out under the personal direction of
Mr. Edward Simpson of Tacoma, Vice-President of the Tacoma
Dredging Company. The secondary approach to Derby Street
43
was constructed in a similar manner by an electrically operated
suction dredge with 20-inch diameter pipe equipment. The
maximum distance the material was carried was about 6,500 feet.
There were several slips or subsidences of the supporting
land caused by placing the great weight of the embankment on
it, but they were less in number or in aggregate amount than
had been anticipated or suggested by the speciflcations. The
subsidences of the land probably average less than one foot over
the whole area of the embankments, but in three locations there
were considerable subsidences, of which two instances required
merely the reconstruction of some bulkheads and the placing of
additional material. The third and most serious was a subsi-
EMBANKMENT CONSTRUCTION.
Looking lonurd I'ortlniid nlong thp complctnl L'nion Avenue Approach embankinent.
Widlh belween friices 40 St., pavfiiiriit 3D ft. Height of ftnbaiikmrnt above surrounding
ground about 25 ft.
dcnce combined with a slide at the south side of the Columbia
Slough, which, although causing only comparatively small loss
of embankment, destroyed the practically finished pier No. 27 in
the slough. The weight of the wet sand embankment on the soft,
oozy bottom of the slough and on the somewhat slippery bank
was too much for the stability of the supporting material, and a
part of the bank and the new sand just placed slid out into the
slough, causing the damage to the substructure. The buried pier
"F" on the land side of the slip was not disturbed by the move-
ment, and the similar construction on the opposite side of the
slough had been completed and was standing satisfactorily. Ad-
ditional embankment was placed for the portion which had sub-
sided. The pier was then repaired and replaced with additional
foundation piles and new concrete, and the entire construction
was finished without further slides or disturbances.
The pavement construction was somewhat unusual. As the
embankments were practically pure sand, ordinary methods of
preparing the subgrade could not be followed. The specifica-
tions provided that the Contractor might either add clayey ma-
terial to the sand surface in such amounts that the subgrade
could be formed and rolled, or else merely shape up the sand
to correct surface and then pour on enough water to pack the
sand similar to a wet sand beach, hard enough to deposit and
roll the stone, keeping the sand "continuously and thoroughly
wet, hard, and firm until and during the placing of broken stone
or concrete." The latter alternative was followed, but the broken
stone base was rolled only lightly, as continued rolling caused
the stone to work to the sides, and after the base had been shaped
up by the light rolling a cushion coat of bituKthic paving mixture
was applied and the whole thoroughly rolled. The placing of
the bitulithic surfacing by standard methods followed imme-
diately.
FRANCHISE TO PORTLAND RAILWAY, LIGHT &
POWER COMPANY
The matter of Franchises for the operation of cars over the
bridge came to the attention of your Commission soon after the
construction of the bridge was started. At your meeting of
April 30, 1915, you appointed an advisory committee on fran-
chises, consisting of District Attorney Walter H. Evans of
Multnomah County, Prosecuting Attorney James O. Blair of
Clarke County, and Consulting Engineer Ernest E. Howard.
Your Engineers prepared a tentative draft of a franchise which
was submitted and critically passed on by the other members of
the advisory committee, and after the submission of several re-
ports by this advisory committee, with extended discussions by
your Commission and representatives of the various traction
companies interested in the tentative drafts submitted, your Com-
mission on September 1, 1916, adopted a general form of fran-
45
chise, setting forth the general conditions under which special
franchises to any company for the operation of cars over the
Interstate Bridge would be granted. At this same meeting you
granted the application of the Portland Railway, Light & Power
Company for a franchise, and on September 20, 1916, adopted
the draft of the franchise to be offered them, following the gen-
eral conditions established. The acceptance of this franchise
was delayed by the failure of the company to reach an agree-
ment with the city of Vancouver relative to a franchise for cer-
tain necessary tracks in Vancouver. Early in December, 1916,
it appeared that the reaching of such an agreement was quite
unlikely, and as no other company was ready to act, and that,
consequently, there would be no immediate car service across
the bridge, your Commission on December 16, 1916, applied to
the city of Vancouver for a franchise from the end of the bridge
to the south line of Second Street on Washington Street, and on
First Street and Main Street to the south line of Second Street.
On January 2, 1917, your Commission received notice from the
city of Vancouver, pledging the granting of this franchise, and
ordered the placing of the necessary tracks. By this action you
made possible an agreement between the city of Vancouver and
the Portland Railway, Light & Power Company providing for
the completion of the loop in Vancouver from Second and Main
Streets to Second and Washington Streets by way of Third Street,
and secured the acceptance by the Railway Company of the fran-
chise over the bridge. The main provisions of this franchise are
as follows :
(1) Date of expiration of franchise, December 31, 1921. At
expiration of franchise, and failure of Commission and Com-
pany to agree as to its renewal, the Commission have the right
to purchase such of the Company's tracks as are on the embank-
ment forming a part of the structure. If the Commission elects
not to purchase tracks, the Company has the right to remove
same, repairing any damage done to the pavement by such re-
moval :
(2) Franchise granted over only that portion of the structure
between a point on Hayden Island about 200 feet south of the
south end of the Columbia River Bridge and the end of the Com-
mission's tracks at the south line of Second Street on Washing-
ton and Main Streets in Vancouver :
(3) The tracks south of the Columbia River Bridge, placed
by the Company, arc to be maintained by it, as are also the
46
tracks north of the Columbia River Bridge in Vancouver, which
were placed by the Commission. The tracks on the Columbia
River Bridge, owned by the Commission, are to be maintained by
the Commission except as to extraordinary damages due to acci-
dents, etc., when repairs are to be made by the Company :
(4) All overhead trolley construction to be placed and main-
tained by the Company:
(5) The Commission reserves the right to grant a franchise
to other companies, such other companies to have the right to
use the Portland Railway, Light & Power Company's tracks on
the embankments through the purchase of an equal interest in
them:
(6) The Company is to provide 30-minute service between
the hours of 6 a. m. and 11 :30 p. m. :
(7) The Company is to pay a toll of 25 cents per car and
Sy2 cents per passenger for passage one way :
(8) The most unusual feature of the franchise, as compared
with the other franchises granted on the coast, is the provision
that all income in excess of operating expenses and 6% interest
on the actual investment in physical property under the fran-
chise shall be divided 50% to the Company and 50% to the Com-
mission. Included under the cost of operation shall be a charge
for electric current used in the operation of cars, a fair rental of
the cars used to pay for their maintenance and deterioration at
a rate per car mile, a fair percentage for depreciation of the
physical properties within the limits of this grant, and the
amounts paid for tolls for cars and passengers on the bridge.
RIGHT OF WAY
The right of way owned outright aggregates in amount 34.7
acres. In addition to this ownership, the Commission holds
easements covering privileges for slopes of embankments, etc.,
for maintaining roadways over other property, and also United
States permits to build and maintain bridges over the Columbia
River and over Oregon and Columbia Sloughs. As later set out,
the total cost of this right of way was $25,449.63, which includes
$13,814.41 paid out directly for lands and damages and $11,-
635.22 paid out for changing buildings and such work incidental
47
to right of way. This low total right of way cost is in part due
to donations of land for the approaches.
Lands for rights of way were donated by:
The Peninsula Industrial Company; C. C. Colt, President.
The Riverton Land Company; R. V, Jones, President
The Portland Railway, Light and Power Company; Frank-
lin C. Griffiths, President.
The heirs of Fink and Stafford estate.
QUANTITIES
The following are the quantities in the various portions of
the completed structure as calculated for the making of final
payments to the contractors:
I.
COLUMBIA RIVER BRIDGE
(a) Substructure — Contract No. 7
Concrete in shafts and copings of all piers and buried
piers above the tops of bases 5,354.6 cubic yards
Reinforcing metal in piers and buried piers 96,960 pounds
Mass in bases of piers from the bottom of base to
top of base 1 5,806.7 cubic yards
Mass in bases of buried piers, from bottom of base to
top of base _467.6 cubic yards
Piles below the bottoms of bases of piers and buried
piers 78,826 lineal feet
Riprap stone deposited about piers 10,604 cubic yards
For temporary use during construction, the following:
Piles in dolphins for ferry landings for Portland
Railway, Light and Power Company's ferry, and
piles under runways for said ferry — 19,672 lineal feet
Timber and lumber in temporary ferry landings and
in runways for same 298,600 feet board measure
(b) Superstructure — Contracts Xos. 1, 2 and 11.
Metal in truss and girder spans 12,914,084 pounds
Metal in towers and counterweights 823,841 pounds
Street car rails, fastenings, etc 621,360 pounds
Machinery and wire ropes 356,698 pounds
Concrete in counterweights 589.2 cubic yards
Roadway slab and bitulithic paving between outer
faces of curbs 15,316.6 square yards
Net area of sidewalk slab outside of outer face of
curb 2,417.7 square yards
Concrete in railings and ornamental posts 84.3 cubic yards
48
II.
OREGON SLOUGH BRIDGE
Substructure — Contract No. 9
Concrete in shafts and copings of all piers and
buried piers, above tops of bases 1,634.3 cubic yards
Reinforcing metal in piers and buried piers 25,742 pounds
Mass in bases of piers from the bottom of base to the
top of base 2,356.1 cubic yards
Mass in bases of buried piers, from bottom of base to
top of base 394.0 cubic yards
Piles below bottom of bases of all piers and buried
piers 41,302 lineal feet
Riprap stone around piers 6,549.8 cubic yards
Superstructure — Contracts Nos. 5, 6 and 11
Metal work in girder spans.. 2,631,300 pounds
Street car rails, fastenings, etc 202,934 pounds
Roadway slab and bitulithic paving between outer
faces of curbs 4,942.9 square yards
Net area of sidewalk slab outside of outer face of
curb 656.2 square yards
III.
COLUMBIA SLOUGH BRIDGE
Superstructure — Contract No. 9
Concrete in shafts and copings of all piers and
buried piers above tops of bases 838.1 cubic yards
Reinforcing metal in piers 11,784 pounds
Mass in bases of piers from bottom of base to top of
base 704.9 cubic yards
Mass in bases of buried piers from bottom of base to
top of base 493.3 cubic yards
Piles below bottom of bases of all piers and buried
piers 13,366 lineal feet
Riprap stone around piers 1,500 cubic yards
Superstructure — Contracts Nos. 5, 6 and 11
Metal work in girder spans 600,440 pounds
Street car rails, fastenings, etc 55,120 pounds
Roadway slab and bitulithic paving between outer
faces of curbs 1,352.7 square yards
Net area of sidewalk slab outside of outer face of
curb .179.4 square yards
49
IV.
VANCOUVER APPROACHES— Contracts Nos. 10 and 12
Embankment 25,500 cubic yards
Slope protection concrete slabs 2,054.8 square yards
Rock fills at buried piers 618.3 cubic yards
Concrete in curbs 120.6 cubic yards
Excavation on Main street 848 cubic yards
Other excavation 682 cubic yards
Concrete base for paving 1,423 square yards
Broken stone base for paving 614 cubic yards
Bitulithic paving on concrete base 1,423 square yards
Bitulithic paving on broken stone base 2,444 square yards
Concrete sidewalks 1 ,032.2 square yards
V.
EMBANKMENT PORTION OF MAIN APPROACH TO UNION AVENUE
(Includes Hayden Island Embankment.)
Contract Nos. 10 and 12
Embankment 932,300 cubic yards
Excavation for drainage ditches 1,700 cubic yards
Rock JSlls at buried piers 3,624.4 cubic yards
Slope protection concrete slabs 38,942.2 square yards
Excavation for subgrade of paving 2,592 cubic yards
Broken stone base for paving 10,903 cubic yards
Broken stone in macadam paving 802 cubic yards
Bitulithic paving on broken stone base 41,337.4 square yards
Barrier fence 23,515 lineal feet
Concrete sidewalks 262.8 square yards
Broken stone in shoulder for paving 724 cubic yards
Excavation for shoulders 280 cubic yards
VI.
EMBANKMENT APPROACH TO DERBY STREET
Contract Nos. 12 and 13
Embankment . 515,450 cubic yards
Excavation for drainage ditches 988 cubic yards
Rock fills 396.8 cubic yards
Slope protection concrete slabs 10,193.7 square yards
Excavation for subgrade of paving 568 cubic yards
Broken stone in macadam paving 4,556 cubic yards
50
STATEMENT OF COST OF CONSTRUCTION
The following figures are for the bridge and approaches
complete ready for use. No costs of operation or maintenance
since the bridge has been opened to traffic are included, and none
of the income from toll receipts since the bridge has been in
service is considered.
There is first given a tabulation of all expenditures according
to construction contracts with the amounts paid by each County
to each Contractor. (Table A.) There is then given a complete
tabulation of the total cost separated into the principal units of
the structure and into portions paid by each County. (Table B.)
This table includes all the costs according to the construction
contracts and also all the other features not covered by those
contracts, such as right-of-way, engineering fees, etc., and gives
the final total costs of the entire bridge and approaches.
There is then given a statement (Table C) of the financial
condition of each County fund, again referring only to moneys
having to do with original construction cost and not with either
receipts or expenditures for maintenance and operation. It ap-
pears to us that Clarke County has not given full credit to this
fund for interest or moneys held during construction, but may
have diverted the interest to some other fund. If this interest
were credited to the fund the balance on hand would be a little
greater than that shown for Clarke County.
This final statement is followed by a detailed distribution
assigning to each of the items as given in Table B the amounts
from each of the contract numbers as given in Table A. The
principal unit prices are also given.
TABLE A
TOTAL EXPENDITURES AS SHOWN BY THE ENGINEERS' ESTIMATES
FOR EACH CONSTRUCTION CONTRACT
Contract
Number
1
2
5
6
7
9
10
11
12
13
L. S. 1
L. S. 2
L. S. 3
Special Track Work on Vancouver Approach.
Contractor
U. S. Steel Products Co
Porter Brothers
Northwest Steel Co.-
Porter Brothers
Pacific Bridge Co
Pacific Bridge Co
Tacoma Dredging Co -
Warren Construction Co
W^arren Construction Co
Standard American Dredging Co.
Pacific States Electric Co
U. S. Steel Products Co
Nelson and Brown
Total
420,578.10
103,311.71
90,224.01
18,881.75
331,875.66
139,118.25
179,244.82
85,518.29
98,111.92
95,220.61
3,252.32
8,472.40
4,289.33
7,139.99
By Multnomah
County
9 252,346.86
61,987.03
90,224.01
18,881.75
199,125.40
139,118.25
172,988.18
60,776.35
87,889.23
95,220.61
2,784.59
7,580.44
3,217.00
By Clarke
County
1168,231.24
41,324.68
132,750.26
6,256.64
24,741.94
10,222.69
467.73
891.96
1,072.33
7,139.99
Total .- J?l,585,2.19.16
$1,192,1.39.70 9.393,099.16
51
TABLE B
TOTAL COST OF THE ENTIRE STRUCTURE AND THE COSTS OF THE
PRINCIPAL SEPARATE PORTIONS OF THE STRUCTURE
Columbia River Bridge $
Oregon Slough Bridge
Columbia Slough Bridge
Vaucouver Approaches __
Union Avenue Approach
Derby Street Approach -
Lighting System
Ferry Landings _
Tracks on Vaucouver Streets
Right-of-Way
Fees to Engineers
Miscellaneous --
Total
891,005.45
196,944.47
74,942.99
16,086.87
251,220.26
104,877.76
16,014.05
16,890.24
7,139.99
25,449.63
80,000.00
2,984.61
Paid by
Multnomah
County
i 534,603.27
196,944.47
74,942.99
251,220.26
104,877.76
13,582.03
9,342.14
9,316.45
57,142.84
2,522.97
Paid by
Clarke
(bounty
$356,402.18
16,086.87
2,432.02
7,548.10
7,139.99
16,133.18
22,857.16
461.64
$1,683,556.32 $1,254,495.18 $429,061.14
TABLE C
CONSTRUCTION FUNDS— MULTNOMAH COUNTY
RECEIPTS
Sale of Bonds __ $ 250,000.00
Premium on Bonds 3,375.00
Accrued Interest 6,250.00
Sale of Bonds. _ 1,000,000.00
Premium on Bonds... __ 31,900.00
Accrued Interest 2,707.25
$1,294,232.25
DISBURSEMENTS
Coupon on Bonds 6,225.00
Interest on Coupons 25.00
Accrued Interest 2,707.65
8,957.65
Net Amount of Bond Issue $1,285,274.60
Expenditures as given in Table B__ 1,254,495.18
Balance in Construction Fund $ 30,779.42
CONSTRUCTION FUNDS— CLARKE COUNTY
RECEIPTS
Sale of Bonds $ 500,000.00
Accrued Interest and Premium 3,894.50
Net Amount of Bond Issue $ 503,894.50
Expenditures as given in Table B 429,061.14
Balance left from Construction $ 74,833.36
Interest on Bonds paid from Construction Fund 49,375.00
Balance in Construction Fund... $ 25,458.36
52
TABLE D
Classification of expenditures given in Table A, to show cost of various
portions of construction as shown by Table B.
The following are all amounts paid to Contractors on the Engineers'
estimates :
COLUMBIA River Bridge: _, , . ^, ,f «^^ *^>' ^ ..f'^l^^^'
Total Multnomah Co. Clarke Co.
Contract No. 7 Substructure ..- ^307,501.00
Contract No. 1 Steel 419,992.24
Contract No. 2 Erection _ 101,458.57
Contract No. 11 Floor 61,854.84
1890.807.31 $53 4, 184.39 $350,322.92
Oregon Slough Bridge:
Contract No. 9 Substructure .1? 89,895.10
Contract No. 5 Steel 73.150.61
Contract No. 6 Erection 15,319.45
Contract No. 11 Floor -.. 18,579.31
$196,944.47 All paid by Multnomah Co.
Columbia Slough Bridge:
Contract No. 9 Substructure $ 49,223.15
Contract No. 5 Steel 17.073.40
Contract No. 6 Erection _ 3,562.30
Contract No. 11 Floor 5,084.14
$ 74,942.99 All paid by Multnomah Co.
Vancouver Approaches:
Contract No. 10 Embankment $ 6,256.64
Contract No. 12 Paving -.. 9,830.23
$ 16,086.87 All paid by Clarke Co.
Union Ax-enue Approach (including Hayden Island construction):
Contract No. 10 Embankment $172,988.18
Contract No. 1 2 Paving 78,232.08
$251,220.26 All paid l)y Multnomah Co.
Derby Street Approach:
Contract No. 13 Embankment $ 95,220,61
Contract No. 12 Paving 9,657.15
$104,877.76 All paid by Multnomah Co.
Paid by Paid by
Lighting System: Total Multnomah Co. Clarke Co.
Contract LSI - -^ .3,252.32 $ 2,784.59 | 467.73
Contract LS2 __ 8,472.40 7,580.44 891.96
Contract LS3 - 4,289.33 3,217.00 1,072.33
$ 16,016.05 $ 13,582.03 « 2.432.02
Ferry Landings, Etc.:
Contract No. 7 Temporary Construction $ 15,570.24 $ 9.342.11 $ 6,228.10
Tracks on Vancouver Approach :
Contract— Special $ 7,139.99 All paid by Clarke Co.
Right-oi'-Way :
The following items, which are here classified under Right-of-Way. include the
amounts paid to Contractors for work such as raising and altering buildings, removing
53
car barn and street car property, etc. The amounts paid directly for right-of-way are
given elsewhere:
Paid by Paid by
Total Multnomah Co. Clarke Co.
Contract No. 1 $ 585.86 $ 351.52 | 234.34
Contract No. 2.-. 1,853.14 1,111.88 741.26
Contract No. 7 8,803.76 5,282.26 3,521.50
Contract No. 12. 392.46 392.46
$ 11,635.22 I 6,745.66 $ 4,889.56
TABLE E
Classification of items paid to others than the above Contractors and
by the Commission directly — not through Engineers* estimates:
By Multnomah By Clarke
Count>' County
Columbia River Bridge (extra ticket houses)-. $ 118.88 | 79.20
Ferry Landings (land rent)... 1,320.00
Right-of-Way (lands purchased and damages paid) 2,570.79 11,243.62
Fees to Engineers 57,142.84 22,857.10
Miscellaneous (includes advertisements, printing, attorneys' fees
and other incidental expenses) 2,522.97 461.64
f 62,355.18 $ 35,961.68
TABLE F
UNIT PRICES
The principal unit prices paid to the Contractors are as follows:
Columbia River Bridge:
Concrete In pier shafts $ 9.00 per cubic yard
Mass in bases of piers 12.00 per cubic yard
Piles below bases of piers 46 per lineal foot
Piles in ferry slips... ( Temporary use during ) 25 per lineal foot
Timber in ferry slips. ( construction j 30.00 per M. B. M.
Rip-rap around piers - - - 2.05 per cubic yard
(solid measurement)
Metal In truss and girder spans^
Manufacture and delivery 2.59c per pound
Erection and painting. : 0.55c per pound
Metal in towers —
Manufacture and delivery 3.43c per pound
Erection and painting _. 0.90c per pound
Electric railway rails, etc. —
Manufacture and delivery -- 2,755c per pound
Erection - 0. iOc per pound
Machinery and ropes —
Manufacture and delivery _. lO.OOc per pound
Erection and painting. 1.25c per pound
Concrete in counterweights. i^ll.OO per cubic yard
Concrete roadway slabs and bitulithic paving 3.18 per square yard
Oregon and Columbia Sloi'gh Bridges:
Concrete in pier shafts. ?10.00 per cubic yard
Mass in bases of piers 16.00 per cubic yard
Piles below bases of piers. 35 per lineal foot
Rip-rap around piers 2.00 per cubic yard
(solid measurement)
Metal in girder spans- —
Manufacture and del ivery 2.55c per pound
Erection and painting 0.55c per pound
54
Electric railway rails —
Manufacture and delivery - 3.00c per pound
Erection - 0.40c per pound
Concrete roadway slab and bitulithic paving |3.48 per square yard
Concrete sidewalk slabs -.. .- 2.10 per square yard
Approaches — In Vancouver :
Embankment in place (net) _ 13.24c per cubic yard
Hock fills - ^2.00 per cubic yard
(solid measurement)
Concrete slope protection slabs _ _ .80 per square yard
Curbs _. _ - 11.00 percubic yard
Sidewalks - 80 per square yard
Concrete paving base - .70 per square yard
Broken stone in paving base :.- - 1.39 per cubic yard
(loose measurement)
Bitulitliic paving on concrete base _ 1.15 per square yard
Bitulithic paving on broken stone base 1.17 per square yard
Hayden Island and Union Avenue Approach:
Embankment in place _ 13.24c per cubic yard
Rock fills ._- - - _ $2.00 percubic yard
(loose measurement)
Concrete slope protection slabs. _ _ .80 per square yard
Broken stone in paving base _ 1.48 per cubic yard
(loose measurement)
Bitulithic paving on broken stone base _ 1.17 per square yard
Barrier fence (timber) _ 36 per lineal foot
Broken stone in shoulders _ 1.95 per cubic yard
(loose measurement)
Derby Street Approach:
Embankment in place. _ lC.48c per cubic yard
Slope protection slabs _ _ 90.00c per square yard
Rock fills - - _ ^2.15 percubic yard
(solid measurement)
Broken stone in macadam pavement _ _ 1 .95 per cubic yard
( loose mea su rement )
MAINTENANCE
In the Columbia River Interstate Bridge and approaches you
have a property which should be maintained in good condition.
So maintained, there is hardly any limit to the life of the struc-
ture; but indifferently maintained, deterioration might come
about with comparative rapidity.
(1) Paint:
The feature most subject to deterioration, aside from the
pavement, is the steel superstructure work. To prevent rust the
structure must be kept painted. For the purpose of future guid-
ance in buying paint different makes of standard bridge paints
were used — on different parts of the structure. You have thus
a large, practical, comparative test of the different paints. As
nearly as practicable, all paints were handled and applied uni-
formly, so that the paint which lasts longest, excepting accidents,
should be considered the best paint for your location and con-
ditions.
55
The paints used and the parts where they are used are as
follows (Spans are numbered from Vancouver, the left span is
No. 3) :
Columbia River Bridge — Spans 1, 2, 3 and 4, and Towers:
Shop coat, Tockolith; first field coat. No. 1379 R. I. W. maroon; second field coat.
No. 49 R. I. W. black. Made by Toch Brothers, 320 Fifth avenue. New York, N. Y.
Columbia River Bridge — Spans 5, 6, 7, 8 and 9:
Shop coat, red lead lute; first field coat, Metalkote brown; second field coat,
Metalkote black. Made by Lowe Brothers, 451 East Third street, Dayton, Ohio.
Columbia River Bridge — Spans 10, 11, 14 — ^The Oregon Slough bridge and the Columbia
Slough bridge (except main girders) :
Shop coat, Dutch Boy red lead In oil. Made by the National I^ead Company, 111
Broadway, New York, N. Y. First field coat, Nobrac, brown; second field coat,
Nobrac, black. Made by the Patterson- Sargent Company, .38th street and St. Clair
avenue, Cleveland, Ohio.
Columbia River Bridge — Span 12:
Shop coat, Dutch Boy red lead in oil. Made by the National Lead Company.
First field coat and second field coat, paint furnished by Dunn & Company of Port-
land, Ore.
Columbia River Bridge — Span 13:
Shop coat, Dutch Boy red lead in oil. Made by the National Lead Company.
First field coat and second field coat, paint furnished ])y Rasmussen &. Company of
Portland, Ore.
Columbia Slough Girders:
Shop coat, Tockolith. Made by Toch Brothers. First field coat, Nobrac, brown;
second field coat, Nobrac, black. Made by the Patterson-Sargent Company.
We recommend that a thorough inspection of the steel struc-
ture to determine the condition of the paint be made once a year.
Where such inspection discloses rusting of the metal, the metal
should be thoroughly cleaned with scrapers and wire brushes
and touched up with preferably the same kind of paint as was
used for the original second field coat. This inspection should
also be directed toward the discovery of accumulations of dirt
and trash that will hold moisture and so hasten the destruction
of the paint. All such accumulations should be removed.
(2) Paving:
In consideration of payment already made, the Warren Con-
struction Company is obligated to maintain all bitulithic paving
in repair for a period of five years. This will be till March 1,
1922. This maintenance contract also gives your Commission
the option of requiring this company to undertake the mainte-
nance of such paving south of the Columbia River bridge for a
second period of five years, the exercise of such option binding
your Commission to pay this company annually for such second
five-year period IVjC per square yard of pavement covered by
this contract.
56
(3) Machinery:
By section 31 of the Specifications, the United States Steel
Products Company is required to replace any and every part of
the machinery furnished by it which may prove defective within
one year from the putting of the bridge into service, or prior to
February 14, 1918. The machinery should receive regular care
and inspection with special attention at all times to the proper
lubrication of moving parts.
(4) Wire Ropes:
The attention of your Commission is particularly called to
the maintenance of the wire ropes on the lift span. With proper
attention these should not require renewal for many years, but
it is essential that they be protected from rusting. Your Engineers
recommend that in the summer of 1918, when the weather is
warm, that the ropes be thoroughly cleaned of their present dress-
ing and then treated with some first quality wire rope dressing
made especially for ropes exposed to the elements and infre-
quently operated. Successive applications of dressing should be
made as needed, so that rusting of the wires in the ropes may be
entirely prevented. The ropes should be carefully inspected
twice a year, early in the spring and late in the fall.
(5) Substructure:
The piers themselves are subject to practically no deteriora-
tion, although about ten years from this date it would be well to
have them cleaned and painted with a wash of lime and cement.
However, there has been placed a quantity of rip-rap, composed
of stones varying in size from 1/3 cubic foot to IM2 cubic yards,
around each pier. The object of this rip-rap is to prevent mate-
rial scour of the river bed adjacent to the piers. Once a year
for the next five or six years, after the high waters have passed,
soundings should be made around the piers. If the rip-rap is
found to be lower than about twelve feet above the elevation of
the bottom of pier base for the Columbia River piers, or six
feet above the bottom of pier base in the sloughs, some additional
rip-rap of the same kind should be deposited. The elevations of
bottoms of pier bases is shown on the drawings. In this connec-
tion, we desire to call to your attention that only a small amount
of rip-rap has been placed at piers 11, 12 and 13, owing to the
sand bar, whose top is above the top of these pier bases. In
case the river channel should shift and this sand bar disappear,
it will be necessary to place considerable rip-rap around these
piers.
57
(6) Embankments:
Embankments, especially where resting on soft subsoils, and
against which there may be overflow, are subject to deterioration
or damage through several years and often do not finally con-
solidate for a long time. Your approach embankments have now
passed through two seasons of high water of more than ordinary
height with comparatively and actually small amount of damage.
We believe this substantially perfect condition due to the manner
in which the embankments were built, and we do not think you
need be apprehensive of any very general or serious subsidence.
For the protection of the slopes of embankments from erosion
concrete slabs were constructed over parts of the slopes. In the
main part these have held satisfactorily, but portions of the
slabs on the Vancouver embankment washed down in the high
water of 1917 and were replaced by rip-rap stone. The setting
up of pronounced current with eddies might cause similar diffi-
culties at the ends of the embankments on Hayden Island or at
the slough crossings. However, the present cheaper construction
may hold indefinitely and there is no need to place more stone
now. For several years at times of extreme high water you
should have embankments patrolled throughout, giving particu-
lar attention to the ends, so that cutting or washing may be
stopped in incipient stages. These embankments are not unlike
river levees and during their first five or six years should receive
the same sort of patrolling during high waters. We consider it
significant that the damage done by the 1917 high water was on
a portion of embankment not constructed at the time of the
previous high water, and that no damage was caused by the 1917
high water at the points where the chief damage was done in 1916.
Considerable expense has been entailed by the fertilizing
and seeding of the slopes of the embankments, in order to provide
a sod to prevent erosion and weathering of the slope. The results
so far accomplished indicate that the securing of a compact sod
is possible, but it may be necessary to refertilize the slopes and
replant parts of the same from time to time for several years to
secure satisfactory results. Attention should be given to this
planting and also the roses and broom planted along the ap-
proach railings.
Evergreen blackberries were set out along the lower portions
of the embankment slopes of the approach embankments with a
view to developing in time a hedge sufficiently thick to keep
cattle from climbing the sides of the embankments. Most of these
bushes did not survive their first high water and it was concluded
58
wise not to replace them until after some sod had been formed
over the sand. In the meantime, a light barbed wire fence was
built along the bottom of the embankment to keep off the cattle.
It is suggested that as the grass and other growths develop on
slopes of embankments it will be well to set large nmnbers of
evergreen blackberries, as at first intended, so that a hedge may
develop. The cost of such planting will be small, but if carried
out should make unnecessary the replacement of the present
wire fence.
(7) Power Supply:
Soon after the bridge was put into service it appeared that the
electric power supplied by the Portland Railway, Light and
Power Company from their long feeder line from Portland did
not hold up sufficiently in voltage to give prompt and speedy
operation of the lift span. After investigating various possible
sources of electric power supply, your Engineers recommended
the installation of a rotary transformer at Vancouver so that
adequate power might be there supplied, independent of the
street car power line. This equipment has been ordered by your
Conmiission and after it is installed there should be no further
difficulty on account of low voltage.
TOLLS
Effective February 1, 1917, your Commission issued schedule
of tolls as follows :
Rates in
Item SINGLE TRIP cents except
No. PERSONS as shown
1. Pedestrians, each (one person) . See note 5
2. One person on bicycle (including bicycle). See note 5
3. Two persons on one bicycle (including bicycle.) See note 10
4. Kach person riding upon an animal (not including animal). Sec note 5
5. Each person riding upon a vehicle not operating on a schedule, approved by
the Commission. See note 5
6. Each person riding upon a vehicle operated on a schedule, approved by the
Conmiission, which schedule shall require regular operation of vehicles at
least once an hour for twelve (12) consecutive hours per day. See note 4
7. Each person riding upon a vehicle operated on a schedule of service approved
by the Commission, which schedule shall require regular operation of
vehicles at least every forty (40) minutes for seventeen (17) consecutive
hours per day. See note 3\U
Note — Children 7 years of age and over, full fare; under 7 years of age, free.
LIVE STOCK AND ANIMALS
8. One animal driven, led or ridden, of cattle, goats, hogs, horses, mules and sheep. 5
9. For drove of animals including cattle, goats, hogs, horses, mules and sheep on
foot, ten head and under, each 5
10. For each head, over ten head, in one lot _ 2
59
SELF-PROPELLED VEHICLES
1 1 . Motorcycles 5
12. Passenger vehicles having seats for two persons (one-seat runabouts). 10
13. Passenger vehicles having seats for not more than eight persons.- 15
14. Passenger vehicles and cars having seats for more than eight persons 25
15. Trucks or motor delivery wagons commonly called of one-half ton capacity 10
IC. Trucks not over one ton capacity 15
17. Trucks over one ton, l)ut not over two ton capacity 25
18. Trucks over two ton capacity 50
19. NVfMjd sawing machines 15
20. Self-propelled vehicles moving under their own power, not otherwise specified,
including farm engines and road rollers 50
21. Trailers drawn by self-propelled vehicles, for each trailer 15
22. Freight cars running on railway tracks, either self-propelled or drawn 75
23. Electric locomotives $2.50
The rates of items No. 11 to No^ 23, inclusive, are exclusive of passengers,
operators, drivers or persons in charge, except that for passenger vehicles or
cars capable of seating more than twenty-five passengers, two persons shall
be carried free, provided tliey are engaged in operating the same.
VEHICLES DRAWN BY ANIM.\LS
24. One velilcle drawn by one animal 10
25. One vehicle drawn by two animals ._ 15
26. One vehicle drawn by three animals 25
27. One vehicle drawn by four animals 35
28. One vehicle drawn by six animals — 50
29. Each additional vehicle in tow 10
30. Each additional animal -. 5
INCOME AND TRAFFIC
The income from tolls for the first ten months is given in the
following table:
Electric
Hallway
1917 Tolls
February (14 days) I l,702.7fi
March 3,518.91
April 5,011.13
May 4,605.58
June - - -- 4,930.97
July -- 5,925.84
August .-
Sepetmber —
October
November 5,550.63
Total (289 days)
Vehicle
])aily
Tolls
Total
.\verage
$ 2,019.84
$ 3.722.60
$265.90
4,472.74
7,991.65
257.79
6,218.11
11,229.24
374.30
7,066.75
11,672.33
376.53
9,308.60
14.239.57
474.65
11,426.87
17,352.71
559.76
17,650.91
569.38
15,479.57
515.98
15.511.26
500.36
8,583.6 1
14,134.27
471.14
S!tl28,984.11
IK 146.31
The average daily receipts have been ?446.31, and the highest
$837, which was taken in on July 4th. The interest on moneys on
hand brings up the total average daily receipts to $448.53. The
income, therefore, is surpassing the most sanguine expectations.
The total daily average operating and maintenance expense over
the same period has been about $80. The bridge is therefore
more than self-supporting; and, if present conditions continue,
it will pay for itself in a few years. The counties have actually
60
acquired this valuable property by making use of their credit
and wholly without adding to the burden of general taxation.
Counts of the traffic are taken periodically and in time will
afford interesting data of the traffic development. For instance,
even at the present time more than ten times as many self-
propelled vehicles as horse-drawn vehicles cross the bridge. It
is notable also how much freight now goes by motor truck which
did not go by that means when the river had to be crossed by
ferry.
LIFT SPAN MOVEMENTS
The number of operations per month of the lift span varies
with the state of the river and the boat traffic. In an average
month there are from 200 to 225 openings. The average time
which traffic is delayed by each opening is from two to two and
one-half minutes; many times the delay is only one and one-half
minutes. The total time the lift span is open and traffic delayed
is about ten hours per month, which includes night operations.
The navigation, therefore, does not cause much more delay lo
the roadway traffic than a busy street intersection.
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